Chevrolet introduced two new heavy-duty models to its 2015 lineup on Friday.

The automaker introduced updated versions of the Silverado 2500 HD and 3500 HD. The new models are designed with a few updated options that’ll make towing easier and more reliable. The most significant may be improved cooling that will enable the 6.6-liter engine to maintain full power, regardless of heavy loads or sizzling temperatures.

“It is one thing to generate big power numbers in cool weather, and quite another to maintain power and torque when towing up a long grade on a blistering summer day,” said Jeff Luke, executive chief engineer. “We think customers will appreciate all of the work that went into the cooling for the new Silverado HD when they get a chance to really put it to the test.”

Consumers will also find an updated interior. Chevy has increased the space, storage capacity and comfort of the Silverado heavy-duty models.